Branch : Computer Science and Engineering
Subject : Wireless Communication
Saleh and Valenzuela Indoor Statistical Model
Introduction:
Saleh and Valenzuela reported the results of indoor propagation measurements between two vertically polarized omni-directional antennas located on the same floor of a medium sized office building.Measurements used 10 ns, 1.5 GHz, radar-like pulses.
Statistical Model :
The method involved averaging the square law detected pulse response while sweeping the frequency of thetransmitted pulse
The results obtained by Saleh and Valenzuela show that
- The indoor channel is quasi-static or very slowly time varying
- The statistics of the channel impulse response are independent of transmitting and receiving antenna polarization, if there is no line-of-sight path between them.
Saleh and Valenzuela developed a simple multipath model for indoor channels based on measurement results.
The model assumes that
- The multipath components arrive in clusters.
- The amplitudes of the received components are independent Rayleigh random variables with variances that decay exponentially with cluster delay as well as excess delay within a cluster.
- The corresponding phase angles are independent uniform random variables over [0,2π].
- The clusters and multipath components within a cluster form Poisson arrival processes with different rates.
- The clusters and multipath components within a cluster have exponentially distributed interval times.
- The formation of the clusters is related to the building structure, while the components within the cluster are formed by multiple reflections from objects in the vicinity of the transmitter and the receiver.
SIRCIM and SMRCIM Indoor and Outdoor Statistical Models:
- An elaborate, empirically derived statistical model based on the discrete impulse response channel model and wrote a computer program called SIRCIM (Simulation of Indoor Radio Channel Impulse response Models). SIRCIM generates realistic samples of small-scale indoor channel impulse response measurements
- SMRCIM(Simulation of Mobile Radio Channel Impulse-response Models), a similar program that generates small-scale urban cellular and microcellular channel impulse responses